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Home >> Infiniti >> 2003 >> FX45 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P1148: Closed Loop Control Function (Bank 1) Or DTC P1168: Closed Loop Control Function (Bank 2) >> DTC Confirmation Test (Using Generic Scan Tool)
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DTC Confirmation Test (Using Generic Scan Tool)

NOTE: Use the following test to check overall function of closed loop fuel control. During this test, DTC may not be confirmed.
CAUTION: DO NOT use ECM ground terminals when measuring voltage.
  1. Start engine and warm to normal operating temperature. Measure voltage between ground and left front HO2S signal circuit at ECM terminal No. 16 or right front HO2S signal circuit at ECM terminal No. 35, by backprobing.
  2. Monitor voltmeter with engine at 2000 RPM. Voltage should be less than .21 volt at least once and more than .7 volt at least once. If voltage is not as specified, go to DIAGNOSTIC PROCEDURE  . If voltage is as specified, system is okay at this time.
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